Significant advances have been made in the automation of systems for cutting lumber or other types of work pieces. One technique that has significantly automated the lumber processing industry has been the computerized control of sawing operations to optimize the use of an inventory of lumber to produce predefined lengths of boards according to a cut list. In other words, optimizing saw systems exist for allowing an operator to simply enter a cut list into the computerized saw system to define the number of different boards needed of various lengths. According to such systems, the operator simply retrieves standard lumber from an inventory, such as 12 foot lengths, marks the boundaries of defects in the lumber with a light-sensitive chalk, and places the board into the system. Such a system then automatically scans the lumber with a camera to detect the boundaries of the defects, then determines the various lengths of defect free or clear portions of the lumber. When such information is automatically entered into the computer of the saw system, the computer proceeds through an algorithm to determine the most efficient cuts that can be made of the clear portions of the lumber to satisfy one or more lengths required in the cut list, with minimum waste. The saw then automatically advances the lumber from an infeed station to the cutting station, whereupon the saw automatically cuts the lumber and advances it through the cutting system to remove the defects and achieve resulting board lengths that satisfy the cut list. Such a system is known as a PF90 cutting system, available from the assignee of the above-referenced patent application. The PF90 cutting system is capable of storing many cut lists for different application, but such a system cannot sequentially execute between two cut lists in the same operation.
While such types of systems are fully automated and highly advantageous in high volume applications, such systems are correspondingly more expensive than the traditional manual sawing systems where the operators are in full control of the decision making capabilities. There presently exist many manual sawing systems where the operator is aware of the different pieces of lumber needed according to a cut list, and the operator marks the lumber and manually carries out the cutting operation to satisfy the required pieces of lumber. While such systems are effective in achieving the desired result, they are labor intensive and not highly efficient.
Enhancements, in the nature of deployable stop blocks have been added to the manual systems in an attempt to increase the efficiency of the operator. In such enhanced systems, various stop blocks can be deployed in the path of the lumber as it is manually moved through a sawing station to automatically provide stop positions for board cuts to specific lengths. For example, four deployable stop blocks can be arranged downstream from the saw path, each being six inches apart and independently deployable, to provide board lengths of 36 inches, 42 inches, 48 inches and 54 inches. Such systems have undergone further refinements to provide a single stop block that is movable in a linear manner up and down the travel path of the lumber to achieve any desired board length, in increments such as 1/32 inch. In such type of semiautomatic systems, an operator can simply input via a keyboard, or otherwise, a specific length, whereupon the movable stop block is automatically and quickly moved to a specific distance from the cutting path of the saw blade.
From the foregoing, it can be seen that a need exists for further enhancements to manual or semiautomatic sawing systems to increase the efficiency thereof, while yet providing a cost effective cutting system. Yet another need exists for enhancements that can be retrofit to a manual or semiautomatic cutting system, to further enhance the cutting operations and increase the efficiency thereof.